2

VMEchip2

Local Bus to VMEbus I/O Control Register

ADR/SIZ

 

 

 

$FFF4002C (8 bits of 32)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BIT

15

14

 

13

12

11

10

9

 

8

 

 

 

 

 

 

 

 

 

 

 

NAME

I2EN

I2WP

 

I2SU

I2PD

I1EN

I1D16

I1WP

 

I1SU

 

 

 

 

 

 

 

 

 

 

 

OPER

R/W

R/W

 

R/W

R/W

R/W

R/W

R/W

 

R/W

 

 

 

 

 

 

 

 

 

 

 

RESET

0 PSL

0 PS

 

O PS

0 PS

0 PS

O PS

0 PS

 

O PS

 

 

 

 

 

 

 

 

 

 

 

This register controls the VMEbus short I/O map and the F page

 

 

($F0000000 through $FF7FFFFF) I/O map.

 

 

 

 

 

I1SU

 

When this bit is high, the VMEchip2 drives a supervisor

 

 

 

address modifier code when the short I/O space is

 

 

 

 

accessed. When this bit is low, the VMEchip2 drives a

 

 

 

user address modifier code when the short I/O space is

 

 

 

accessed.

 

 

 

 

 

 

 

I1WP

 

When this bit is high, write posting is enabled to the

 

 

 

VMEbus short I/O segment. When this bit is low, write

 

 

 

posting is disabled to the VMEbus short I/O segment.

 

I1D16

 

When this bit is high, D16 data transfers are performed to

 

 

 

the VMEbus short I/O segment. When this bit is low, D32

 

 

 

data transfers are performed to the VMEbus short I/O

 

 

 

segment.

 

 

 

 

 

 

 

I1EN

 

When this bit is high, the VMEbus short I/O map decoder

 

 

 

is enabled. When this bit is low, the VMEbus short I/O

 

 

 

map decoder is disabled.

 

 

 

 

 

I2PD

 

When this bit is high, the VMEchip2 drives a program

 

 

 

address modifier code when the F page is accessed. When

 

 

 

this bit is low, the VMEchip2 drives a data address

 

 

 

modifier code when the F page is accessed.

 

 

I2SU

 

When this bit is high, the VMEchip2 drives a supervisor

 

 

 

address modifier code when the F page is accessed. When

 

 

 

this bit is low, the VMEchip2 drives a user address

 

 

 

modifier code when the F page is accessed.

 

2-50

Computer Group Literature Center Web Site

Page 128
Image 128
Motorola MVME172 manual Local Bus to VMEbus I/O Control Register